A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5855-01-270-6847
NSN 5996-01-241-1843
NSN 5960-01-205-0386
NSN 6150-00-042-9966
NSN 6685-01-126-3061
NSN 5930-01-633-7026
NSN 6130-01-220-6331
NSN 6110-01-313-9030
NSN 5920-00-890-5219
NSN 5910-01-612-5819
NSN 6650-00-078-5773
NSN 5950-00-203-4002